Dark slide



Jan.- 2, 1934.

DARK SLIDE W. SALCHOW v*Filed March 5. 1932 3 Sheets-Sheet l Jan. 2, 1934. 'A w. sALcHow DARK SLIDE Filed March 3, 1952 3 Sheets-Sheet 2 W. SALCHOW Jan. 2, 1934.

DARK SLIDE' Filed March-5, 1932 3 Sheets-Sheet 3 nren'zor:

Patented Jam 2,

DARK SLIDE Willy Salchow, Berlin-Tempelhof, Germany Application Mai-ch s, 1932, serial Nn. 596,505, and in Germany November 30, 1928 14 claims.

. My invention relates to dark slides for photographic apparatus. It is particularly suitable for apparatus for photographing what is known as copy, i. e., letters, documents, maps, book pages and the like, but may be used for any other purpose, ii' desired. An apparatus for photographing"copy is described in my application for patent of the United States, Serial No. 564,363,

led September 2, 1931, for Photographic apparatus. It Acoxnprisesa copy holder which is normally horizontal and an objective by which the image of the copy is projected vertically onto a mirror and reected horizontally onto a vertical sensitized web oi' paper or the like in the dark slide.

The dark slide according to the present in- A vention is equipped with the usual vertical slidable 4covering plate in combination with means for feeding the sensitized paper to be exposed by, and in time with, the movement of the covering plate. Means of thiskind are described in another copending application'lor patent of the United States, Serial No. 567,625, filed by me October 8, 1931, for Dark slide for photographic apparatus. In this apparatus a feeding mechanism including a feeding cylinder with means forrotating it, and mechanism operativelyconnected tothe feeding mechanism for reciproeating the covering plate are provided.

It is an object of my invention to provide a simpler mechanism which is particularly suitable for comparatively cheap apparatus.

To this end, in combination with the means for reciprocating the covering plate, I provide a l gripper whichiis operatively connected to the reciprocating means and adapted to engage the sensitized paper upon the descent, and to release l forming part thereof a dark slide embodying my inventionl is illustrated diagrammatically `by way of example.

In the drawings Fig. 1 is a central vertical section of the dark slide,

Fig. 2 is a horizontal section on the line II--lI in Fig. l,

Fig. 3 is a vertical section on the line III- III in Fig. 1, A

Fig. 4 is a central vertical section of the dark slide which is similar to the section in Fig. 1 but is drawn to a larger scale and shows only a portion of the lower front end of the dark slide,

Fig. 5 is a section on the line V-V in Fig. 4, Y Fig. 6 is a detail of the handle by which the -dark slide and the gripper are operated, and its accessories, Fig. 'l is an elevation showing the dark slide attached to the rear end of a photographic apparatus, and a collector attached to the dark slide at its bottom, and

Fig. 8 is a similar elevation showing a desensitizing tank attached to the dark slide. i

Referring now to the drawings, and Ailrst to Fig. 7 for the general arrangement, 2 is a por- ,65 tion of a photographic apparatus, 3 is one of its legs, 1 is the dark slide which is iltted to the rear end of the apparatus 2 by means which will be described hereinafter, and 7 is a collector which is attached to the bottom oi the dark slide by strips 105.

The dark slide will now be described in detail with reference to Figs. 1-5. 105e are strips or guides at its front end by which it is detachably connected to the photographic apparatus 2. 31 is the covering plate which is mounted to slide in suitable guides at the rear of the strips l05a, 49 is a sill on which bears the lower end of the covering plate 31 in its closed position, preferably with a strip of felt 49a between the plate and the sill .for keeping out daylight, 50 is an outer transverse bar near the top of the dark slide behind which the covering plate 31 moves, and 51 is an angular transverse covering member at the upper edge of the plate 31 which moves with the plate and bears on the transverse bar 50 in the closed position of the plate 31. 52 is an inner transverse bar which extends at the rear of the covering plate 31 and at the level of the angular member 51 but is secured to the dark slide. 68 is a cover for the rear and upper portions of the dark slide which is mounted to rock about a hinge 72 at its base and at its top has a jib '73 iitting a shoulder at the inner transverse bar 52'. 10 is an inclined mirror on the top plate of the cover 68.

53 is a bracket which is attached to the inner face of thecovering plate 31, 54 is a tubular rod which is secured to, and extends upwardly from, the bracket 53 and through a hole in the inner transverse bar 52, 55 is a slotted resilient tube which is secured to the inner transverse bar 52 at its lower end with a flange and surrounds the tubular rod 54 under resilient frictional pressure so as to hold it in any position to which it may be moved, 56 is a solid rod which is mounted to slide in the tube 54 for operating. the gripper as v will be described, 57 is a nut on the threaded upper end of rod 56 by which the relative movement of the rod 56 and the tubular rod 54, and consequently the relative movement of the rodfand 11 the plate 31, is limited, and 58 is a hollow handle with a pin 59 projecting inwardly from its top for engaging a threaded hole in the upper end of rod 56. 60 is a strip of plush or other suitable material at the front edge of the inner transverse bar 52 and 31a is a mating strip on` the inner face of the covering plate 31. The two strips keep out the light when the covering plate is raised for opening the dark slide.

17 is a compartment in the casing at the rear of the dark slide 1 in which a supply of sensitized paper 15 is mounted on a shaft 16. The compartment 17 is closed at the rear by a vertical wall 14a, at the front by a vertical wall 14, at the top by a horizontal slide 61 and at the bOttom by an,

inclined plate 62. The sensitized paper 15 issues from the compartment 17 through a slot between the wall 14 and the slide61, and 18 is a strip of plush or the like at the inner end of slide 61 for preventing access of light to' the compartment 17. By these means it is possible to open the cover 68 and the covering plate 31 in full daylight without admitting light to the compartment 17. Only that portion of the sensitized paper 15 which is extracted from the compartment 17past the strip 18 at the inn'er end of the slide,-and taken down to the gripper on the covering plate 31 which will presently be described, is spoiled by the daylight when the dark slide is prepared for operation.

The paper, after leaving the compartment 17, is

first` taken up round a saddle 18 at the upper end of the vertical wall 14 and then down along a v vertical wall 20 the upper end of which is secured to the saddle. The wall 20 is'shaped like the letter U as best seen in Fig. 5, with a horizontal transverse bar 21 vat its bottom and two upward-'- ly extending shanks which below the'saddle 19.

are connected by a transverse filler 22. The vertical walls 14 and 20 are mounted on a horizontal partition 83 at the lower end of the dark slide which, together with the bottom plate 28, forms a compartment for the paper-severing mechanism. 82 are paper guides at b'oth sides of wall 20.

Means must be provided for stretching the paper. In the present instance, this means is a brake for engaging the paper 15 as it moves across the saddle 19. 23 is a brake block at the free end of a brake rod 26 which is fulcrumed in the casing 1 at 27, and 29 is a spring or preferably a pair of springs, which is securedj on the rod 26 with its free end bearingvonf the shoulder of the inner transverse-har 52 on which it is held by the jib 73 of the cover 6.8 when the cover is closed, so that the brake block 23 is applied to thev paper 15 on the saddle 19 under resilient pressure.

The gripper will now be described. Mounted on the inner face of the covering plate 31 belowl the bracket 53 are a pair of trunnions 32 which are held in arms 33 projecting inwardly from a vertical iiange of the bracket. 34 is a tubular gripper arm which is mounted to rock about the trunnions 32, 35 isI a block of rubber or other resilient material which is inserted at the lower end of the tube, 35a is an arm which projects upwardly from the opposite end of the tube 34, and 36 is a pin by which the arm 35 is connected to the lower end of rod 56, which, as described, is mounted to slide in the tubular rod 54 on the bracket 53, the eye for thepin being slotted to make up for the circular displacement of the arm with respect to the rod whichl is guided in a straight path in the tube 54. 37 is a U-shaped frame which is secured to the inner face of the covering plate 31 below the bracket 53, 38 is -a tubular holder at the rear bar of the frame 37 in ing through slots in suitable angle brackets 43 on the holder 41.v When the covering plate 31 is in its lower ilnal position the lower edge of screen 40 bears on an angle section 83a the horizontal flange of which is secured to the partition 83 by screws 83h in slotted holes 83c for adjusting the section. The vertical flange of the section has its rear face flush with the rear face of the screenA 40 and projects into a slot in the partition 83 which on the opposite side is bordered by an extension 44 at the lower end of the vertical wall 20.

. The mechanism for severing the exposed lower Vend of the web before it is delivered to the collector 7 or tank 200 Fig. 8, is arranged in the chamber between the bottom plate 28 and the partition 83, and is best seen in Fig. 2. 88 is a vertical shaft which is mounted in the partition 83 near'its rear end and 89 is a handle on the end of the shaft which projects upwardly from the partition 83. The handle 89 is located in a niche below the compartment 17 where it is safe fromy unintentional operation. 90 is an arm which is secured on the lower end of the pin 88, and 29a is a cutter at the end of the'arm which is shown as a razor blade by way of example. The cutter 29a is guided by the extension 44 and a bar 45 below the partition 83. 46 and 47 are plate springs at the ends of checks 48 which linut the movement of the arm 90 in opposite directions,

ics

the springs 46 and 47 retaining the arm 90 in its nal positions by friction after it'has performed a cutting stroke.

The exposed and severed sheets of paper drop through an opening 27 in the bottom plate 28. o103 is a slide which extends across the opening 27, 104 are apair of springs at opposite ends of the slide 103 which tend to pull the slide across the opening 27 to close it, and 106 are a pair of pins at opposite ends of the slide 103 which engage in slots 107 in the bottom plate 28. 108 is a dog below the bottom plate 28 which is here shownas an angle section and is secured to the lower ends of the pins 106. 100 is a dog on the collector 7 which engages the dog 108 as the collector is pushed forward along the bottom plate 28 on the strips 105, as fully described in my said copending application Serial No. 567,625. By these means the slide 103 is pushed back against the action of the spring 104 and the opening 27 is fully exposed when the collector is in its final position with respect to the dark slide.

Referring now to Fig. 7, the collector is del signed substantially as described in my said copending application Serial No. 567,625. The strips 105 at the bottornof the dark slide are engaged by strips 106 at the sides of the collector 'This last-mentioned opening has been isc lamp bracket in a suitable compartment of the apparatus, 6 is a lamp on the bracket, 8 is an opening in the rear wall of the collector opposite the lamp 6, and 9 is an opening in its front wall in line with the opening 8. Panes of ruby glass or other suitable inactinic material are inserted a in the openings 8 and 9.

in the normal operation o! the feed. If the image y appears permanently on the mirror 10, this indi- .cates that the paper is not fed properly or that the supply has become exhausted while, if it disappears permanently, this indicates that the collector is illled, as the last sheet which has been severed cannot move down and permanently obstructs the opening 8. 12 is a receptacle with a hinged bottom ap 13 which is mounted to telescope in the collector 7.

Inl operation the cover 68 is opened, the slide 61- is retracted, a supply of sensitized paper 15 is placed in the compartment 17 and the end of the paper is'extracted past the strip 18 at the slide 61. The extracted end is taken up to the y saddle 19 along the wall 14, after the covering vplate 31 has been raised, round the saddle, and

down along the U-shaped -wall 20, and threaded through the guides 82 at thefsldes-of, this wall. The lower end of the paper is then engaged by the gripper blocks 35, 39 on the covering plate 3l. The cover 68 and the covering plate 31 are now closed and the dark slide is ready for operation.

Instead of the fixed compartment 17 with the slide 61 for the reception of the supply of sensitized paper 15, Iv may provide a casing for the supply which is mounted to rock about trunnions in the side walls of the dark slide and from an opening of which the sensitized paper is extracted, as described in my said copending application Serial No. 567,625.

The block 35 of the gripping mechanism is applied to the paper 15 and in turn applies the paper 15 to the block 39 under the weightof the rod 56and the handle 58. These parts are comparatively light so that the paper is not subjected to excessive pressure by the blocks which must be avoided as such pressure may produce halo. When it is desired to open the covering plate 31, the handle 58 is raised. This causes the tube 34 to rock about its trunnions 32 until the upper .end of it.r arm 35a engages below the bracket 53 and positivelyconnects the rod 56 to the bracket so that upon further raising the handle 58 the covering plate 31 is positively entrained while at the same time the block 35 is disengaged from the paper 15. The 'covering plate 31 is opened as far as required for the size to be exposed and the tubular rod 54 moves with the covering plate to which it is connected by bracket 53. When the covering plate is to be closed the handle 58 is depressed and slides down in its tube 54 until the nut 57 at the 'upper end of the rod 56 bears on the upper end of the tube. The tube, the covering plate and the rod are now positively connected and the block 35 is applied to the paper 15, the paper being gripped by the blocks 35 and 39 andy thereby entrained with the a margin is formed at its bottom the height of covering plate 31. As mentioned, excessive pressure must not be exerted on the paper between the blocks and the maximum pressure is regulated by adjusting the nut 57. When the covering plate 31 has been arrested by the sill 49 in its lower ilnal position the cutter 29 is operated and the exposed lower end of the paper is dropped into the collector 7.

Margins are formed automatically at the sides of the paper by the guidesA 82. When the covering plate 31 has been raised the screen 40 moves down by gravity and deilnes a margin at the upper end of the exposed area. The paper 15 extends down to the level of the cutter 29 and 90 which is equal to the depth of the vertical ange of section 83a. The distance through which the screen 44 projects down from the holder 41 on the covering plate 31, must obviously be twice the depth of the vertical flange of section 83a.

Instead of the collector 7 I may attach a desensitizing tank 200 to the lower end o f the dark slide 1 asA shown in Fig. 8. The tank 200 is lled with a liquid by which the paper is rendered insensitive to daylight to such an extent that it can be removed at actinic light. The action of the desensitizing liquid is so rapid that `a piece oi' paper which has been severed by the cutter 29 and dropped into the sensitizing tank 200, is fully desensitized when it arrives at the opposite end 201 of the desensitizing tank. Therefore it is not necessary to provide means such 'asa ap at this end for keeping out the light. Preferably curved rails 203 are provided in the desensitizing tank for preventing sticking of the paper to its wall.

Any modern desensitizing liquid may be employed. A suitable liquid is a 1:1000 solution of pinakryptol yellow. This solution while not imparting any color to the paper is so effective that good copies are obtained' if the apparatus is not 115 exposed to full day or sun light, i. e. placed in a dark corner of a room, or the blinds of a sunny room are drawn. f- Instead of a vdesensitlzing tank a developing tank (not shown) may be attached to the dark slide 1 but as the copies normally require individual developing it is preferable to desensitize them in the manner described whereupon each copy may be developed as required.

I wish it to be understood-that I do not desire to be limited to the exact details of construction shown and described, for obvious modiilcations will occur to a person skilled in the art.

In the claims affixed to this speciiication no vselection of any particular modication of the invention is intended to the exclusion of other modiiications thereof and the right to subsequently make claim to any modiiication not covered by these claims is expressly reserved.

I claim 1. A dark slide for photographic apparatus in which a ilexible web is employed as the bearer of a sensitive solution comprising a covering plate, means for reciprocating s'aid plate mounted on said plate so as to move with respect thereto, a gripper on said covering plate, and means under the control of said reciprocating means for causing the gripper to engage the-web upon the descent, and to release it on the ascent, of said covering plate. '145 2. A dark slide for photographic apparatus in which a iiexible web is employed as the bearer of a sensitive solution comprising a covering plate, means for reciprocating said plate mounted on said plate so as to move with respect thereto, a 15G asf gripper on said covering plate, means under the control of said reciprocating means for causing the gripper to engage the web upon the descent, and to release it on the ascent, of said covering plate, and means for positively connecting said plate-reciprocating means to said plate in the web-engaging and in the web-releasing position of said gripper.

3. A dark slide for photographic apparatus in which a ilexible web is employed as the bearer of a sensitive solution comprising a covering plate,` a rod mounted to slide on said covering plate and' projecting from said dark slide, a movable gripping member on said plate operatively connected to said rod, a iixed gripping member, also on said plate, for engaging the web in cooperation with said movable member, and means on said movable member for positively connecting said rod to said covering 'plate when said movable member is in its web-releasing position.

4. A'dark slide for photographic apparatus in which a ilexible web is employed as the bearer of a sensitive solution comprising a covering plate,y

a rod mounted to slide on said covering plate, a grippingmember mounted to rock on said plate and operatively connected to said-rod, a lixed gripping member, also on said plate, for engaging the web in cooperation with said rocking member,

andmeans on said rocking member for positively connecting said rod to said covering plate when said movable member is in its web-releasing position.

5. A darli slide for photographic apparatus in which a iiexible web is employed as the bearer o! a sensitive solution comprising a covering plate, a frame on said covering plate, a gripping mechanism i'or 'ensasing the web mounted on said frame and including a fixed and a movable member, a rod mounted to slide on'said covering plate and operatively connected to said movable member at its lowerend, the upper end of said rod projecting from said dark slide, a bracket on said coveringplate, means on said movable member adapted to engage said bracket and to positively connect lsaid rod to said plate when said movable f' vmember is in` its web-releasing position, and

means for positively connecting said rod to said plate when said movable member is in its webengaging position.

6. A dark, slide for photographic apparatus in" which a ilexible'web 'is employed as the bearer oi' a sensitive solution comprising a covering plate, a frame on said covering plate, a gripping mechanism for engaging the web mounted on said frame and including a fixed and a movable member, a rod mounted to` slide on said covering plate and operatively connected to said movable -mexnber at its lower end, the upper end-of said rod projecting from said dark slide, a bracket on said covering plate, means on said movable member adapted t0 engage said bracket and to positively connect said rod to said plate when said movable member is in its web-releasing position, means for positively connecting said rod to said plate when said movable member is in its web-engaging position, and means for limiting the movement of 'said rod with respect to said covering platey in the closing direction'of said covering plate.

'1. A dark slide for photographic'apparatus in which a flexible web is employed as the bearer of a sensitive solution comprising a covering plate, means for reciprocating said plate, a gripper on said covering plate, a tubular rod secured to said covering plate at its lower, and projecting from said dark slide with its upper end, a solid rod mounted to slide in said vtubular rod with its upper end projecting from said tubular rod, a handle at the upper end of said solid rod, means v operatively connecting the lowerend of said solid rod to said gripper, and means for limiting the I relative movement oi said solid and said tubular rod for the movements said solid rod performs for causing said gripper to engage, and for causing it to release, the web.

il. A dark slide for photographic apparatus in which a. iiexible web is employed as the bearer of a sensitive solution comprising a covering plate, means for reciprocating said plate, a gripper on said covering plate, a Itubular rod secured to said covering plate at its lower, and projecting from said dark slide with its upper end, a solid rod mounted to slide in said tubular rod which its upper end projecting from said tubular rod, a tube on said dark slide which engages said tubular rod under resilient preure, a handle `at the upper end of said solid rod, means operatively connecting the lower end of said solid rod to said gripper, and means yfor limiting the relative movement of said solid and said tubular rod 100 for the movements said solid rod performs for causing said gripper to engage, and for causing it to release, the web.

9. A dark slide for photographic apparatus inv which a flexible webis employed as the bearer of a sensitive solution comprising a covering plate, means for reciprocating'said plate, a gripper on said covering plate, means under the control of said reciprocating means for causing the gripper to engage the web upon the descent, and to release it on the ascent, of said covering plate, means for severing the exposed lower end of the web, and means for covering the marginal portions oi' said web against exposure.

10. A dark slide for photographic apparatus in which a flexible web is employed as the bearer of a sensitive solution comprising a covering plate, means for reciprocating said plate, a gripper on said covering plate, means under the control of said reciprocating means for causing the gripper to engage the web upon the descent, and to release it on the ascent, of said covering plate, means for severing the exposed lower end of said web, means on said dark slide for covering a margin at the bottom ofthe exposed sheet against exposure, and' a screen mounted to reciprocate on said covering plate for covering a margin at the top of the exposed sheet against exposure.

il. A dark slide for photographic apparatus in which a flexible web is employed as the bearer of a sensitive solution comprising a covering plate, means ior reciprocating said plate, a gripper on said covering plate, means under the control oi said reciprocating meansfor causing the gripper to engage the web upon the descent, and to release it on the ascent, of said covering plate, a partition at the lower end oi.' said dark slide having a slot for the web to move through, an adjustable member on said partition partly projecting into said slot for regulating its width, a cutter arranged below said adjustable member,

. a bottom plate on said dark slide below said cutter having a slot registering with the slot in said partition, a slide for closing the slot in said botadapted to be engaged by said receptacle and to move said slide so as to expose the slot in said bottom plate when said receptacle is in its final position.

12. A dark slide for photographic apparatus in which a flexible web is employed as the bearer of a sensitive solution comprising a covering plate, means for reciprocating said plate, a gripper on said covering plate, means under the control of said reciprocating means for causing the gripper to engage the web upon the descent, and to release it on the ascent, of said covering plate, a cutter for severing the exposed lower end of said web, a pair of checks defining the two final positions of said, cutter, and means tending to hold said cutter in each of its final positions.

13. A dark slide for photographic apparatus in which a flexible web is employed as the bearer of a sensitive solution comprising a covering plate, means for reciprocating said plate mounted on said plate so as to move with respect thereto, a gripper on said covering plate, means under the control of said reciprocating means for causing the gripper to engage the web upon the descent, and to'release it on the ascent, o! said covering plate, means i'or holding a supply of the flexible web in said dark slide, and means arranged intermediate said gripper and sald.

gripper, a brake block arranged in such relation to said saddle as to bear on the web as it moves about said saddle, and resilient means for exerting pressure on said brake block.

WILLY SALCHOW.

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